COMPARATIVE STUDY OF ROOF WIND PRESSURES FOR PERMEABLE BUILDINGS

Building roof pressures are traditionally determined
in Malaysia based on provisions of BS 6399-2:1997 or MS 1553-
2002. They have performed well under normal conditions of
loading but have been observed to fail under extreme wind
conditions as in a windstorm. This paper presents the analysis of
wind code provisions in the four major codes (BS 6399-2:1997,
MS 1553-2002, EC 1991-1-4:2005 and IS 875-3-1987) on the
general and local wind pressures considering the permeable
rectangular buildings with different roof types in Malaysia. For
numerical comparison, the maximum wind speed recommended
in MS 1553-2002 namely 33.5 m/s has been used. The major
differences in the codes include averaging time for wind speed,
reference height of buildings, values of internal and external
pressure coefficients. Eurocodes has been included in the context
of its introduction in Malaysia, and IS 875-3-1987 is another code
from the tropical zone namely India. The study examines the
conservativeness or not of the codes if used in the Malaysian
context, even though they have been developed for a different
wind climate and region. The results of the study are reported.